In the wake of technological progress and rise in the standard of living, many countries are facing an aging society. Health issues are also gaining increased attention along with aging. Among the aged population are many patients with nervous system disorders and cerebrovascular diseases, e.g. stroke, spinal injury, cerebral palsy or brain damage, multiple sclerosis, and central nervous system damage caused by Parkinson's disease. These patients have various degrees of motor dysfunction, even full paralysis or hemiplegic paralysis in severe cases. Furthermore, there are increasingly more cases of injuries to the nervous system or upper/lower limbs due to traffic accidents. Since walking ability is the key indicator of mobility, and the prerequisite for living normally and independently, the day-to-day living of most post-traffic accident patients is affected, bringing certain burden and challenges to the family.
While the majority of patients suffering from central nervous system damage recover their ability to walk independently after surgery or drug treatment, most of them will be affected by some after-effects, e.g. decrease in motor control, joint stiffness and abnormal gait which cause decreased balance, leading to severe impact on mobility, awareness of the surrounding environment and quality of living. Principles and clinical studies of rehabilitation medicine have shown that, besides early surgery and drug treatment, the correct application of rehabilitation training is crucial to the recovery and improvement of motor functions. The earlier patients start rehabilitation training after the acute phase, the better will the result of recovery be. In particular, the basis of the principles of rehabilitation treatment is the flexibility of the brain. Related medical studies have shown that while damaged nerve cells cannot be regenerated, the nerve tissue could recover its lost function by reorganization or compensation of functions, indicating that the brain is flexible. Both animal and human experiments have shown that proper gait training by actively or passively performing specific functions of the limbs repeatedly can stimulate the proprioceptors to make changes to the map in the central nervous system, encouraging flexibility of the brain and spine to relearn one's gait. Currently, rehabilitation treatment is mostly done manually. It requires tremendous time and energy from rehabilitation therapists, severely limiting the efficiency and effectiveness of rehabilitation training. Moreover, rehabilitation equipment used is simple and do not meet patients' requirement for progressive and focused rehabilitation.
With development in intelligent robotics and expansion of the rehabilitation treatment market, the combination of rehabilitation training and robotics will effectively solve problems that occur in traditional rehabilitation training. As the designing of a safe, quantitative, effective and repeatable multipurpose rehabilitation training system has become an urgent problem for modern rehabilitation medicine and treatment, rehabilitation robots have been developed in response to the problem. Rehabilitation robot is an important branch of medical robots, integrating rehabilitation medicine, biomechanics, mechanics, material mechanics, mechanism, electronics, computer science and robotics. Unlike industrial robots, the rehabilitation robot is in direct contact with the human body and operates within the same space as the patient, allowing the patient to achieve comprehensive and coordinate exercise using rehabilitative devices. Controlled by computer, the rehabilitation robot is equipped with corresponding sensors and safety system to automatically adjust training parameters according to actual operation of different patients, achieving optimal rehabilitation result. Thus, rehabilitation robots help patients relearn skills, and increases rehabilitation motivation and result. Not only does it help patients achieve their maximum functional capacity, it also relieves rehabilitation therapists' heavy workload in physical training, allowing them greater energy to focus on rehabilitation related research.
The main reason for gait dysfunction in stroke patients is damaged motor cells and motor conduction caused by brain injury, which leads to diminished active control, and changes to muscle tension and reduced muscular functions. Stroke patients will have abnormal gait or unable to walk, and appear to walk slowly, with difficulty and have unstable balance. In terms of rehabilitation training, traditional single-motion training does improve the patients' physical functions and walking ability to some degree. However, it does not emphasize overall walking training at an early stage, and much energy and time is spent helping patients complete the process from in-bed exercise to body weight shifting and balance maintenance. Furthermore, lower-limb weight-bearing training using walking stick, ambulation aid or parallel bar does not correct patients' gait effectively, and will even cause gait abnormality from increased upper limb strength. BWSTT (Body Weight Support Treadmill Training) is currently one of the most effective and commonly used rehabilitation training method for patients with weakened lower limbs and those with hemiplegic paralysis; its results recognized by medical experts locally and overseas. Weight bearing is the basis for walking normally but patients with weakened lower limbs and those with hemiplegic paralysis have reduced ability to bear weight in their lower limbs, causing difficulty in shifting their body weight, and affecting their body balance and quality of their walking. BWSTT can reduce burden on the legs, allowing patients with inadequate lower-limb muscle to achieve gait training safely, promoting the establishment of normal gait pattern which is conducive to restoring walking function. During the training process, the rehabilitation therapist may appropriately increase weight bearing training and gradually reduces weight support according to each patient's walking ability and gait pattern improvement, and ultimately allow patients to walk bearing full weight. Currently, the most common methods of weight support used in rehabilitation are water walking, and using walking stick and crutch. Water walking requires a swimming pool and the general public may not have access to a swimming pool, which poses great inconvenience for patients' rehabilitation. On the other hand, using a walking stick or crutch will shift the body weight to be borne by the lower limb to the shoulder joint, causing fatigue to the shoulder joint from the additional burden, resulting in short training time and increasing the likelihood of gait abnormality. The lack of balancing function on the walking stick or crutch may also cause patients to fall and get hurt. Furthermore, existing walk-assist robots do not provide adequate weight support and are unable to maintain gait balance. Their hardware parts also take up tremendous space, and must be operated within specific space and location.
Accordingly, the inventor of the present invention has devoted himself based on his many years of practical experiences to solve these problems.